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EXTENSION REPORT

Safe and savory: On fire about food fermentation

I taught two fermentation classes this week and in each of the classes, I posed a simple question to my students: “What would happen if you left a head of cabbage on your kitchen counter for six weeks?” Responses varied from, “it would rot,” “you’d smell it,” “it would be surrounded by a puddle of goo,” “it sure wouldn’t taste very good,” etc.

I then asked the question: “What would happen if you chopped that same cabbage, mixed it with a little bit of salt and then massaged it with your hands until it produced enough of its own juice to fully immerse the cabbage in its own brine?” Answer: “Sauerkraut.”

This is the essence of fermentation. With a little bit of pure sodium chloride (salt) and your own hands, you can get delicious vegetable mixtures that are preserved for weeks or even months with no canners, dehydrators, freezers or fancy kitchen equipment.

Fermentation is one of the easiest methods of preserving food and boasts the most health benefits, least energy consumption and most variety and room for creativity (read: experimentation) over any other type of food preservation method. Some students get scared off by that lawlessness.

In my other food preservation classes, I strive to engrain in students’ heads that they must always use tested and approved recipes. Food preservation is a science, NOT an art, and bending the rules could result in deadly consequences.

The one we worry most about is botulism and interestingly, cases only began showing up in historical records after canning was invented in the 1790s. By creating a sealed, anaerobic environment, we create the perfect conditions for botulism to grow.

Fermentation, on the other hand, has been around for thousands of years, and creates lactic acid bacteria which lower the pH of things like cabbage and kimchi to such a great extent that bad bacteria are far less likely to grow.

Furthermore, fermentation does not require — nay, must not have — an anaerobic environment; jars need to breathe, and burp, and bubble in order to release the carbon dioxide being produced as good bacteria grow. All of this makes fermented foods categorically safer than fresh foods which may have the risk of carrying disease causing microorganisms like e. Coli, listeria, salmonella, mold, etc., or canned foods, which can harbor botulism and staphylococcus.

In anticipation of teaching about fermentation this week, I purchased “The Art of Fermentation,” written by Sandor Ellix Katz. Katz writes in a lyrical, conversational tone that makes you feel like you are sitting at the dining room table with him discussing various ferments. He lends his decades of experience as a fermenter, giving you the confidence to try your first batch of kraut or kimchi and has been lovingly nicknamed “Sandorkraut” by his followers and friends.

In the opening pages of the book, Katz comments on the double entendre that is “culture” in the realm of fermentation.

The first connotation of the word brings to mind agar plates and swabs of bacteria as he discusses the cultures of organisms that are created through fermentation. He writes that a healthy human gut has over 7 trillion bacteria and as we have come to eat highly processed, commercially produced foods, we end up losing a lot of that good bacteria because it is no longer introduced into our bodies through various fermented foods.

The second connotation of culture is that of the broader ancestral, familial, national food culture of which we are a part. Koreans have their kimchi, Germans have their sauerkraut, Italians have their wine and the French have their cheese. All of these cultural fermented foods play into the pleasure of eating in community and sharing a meal with family and friends.

Fermentation brings flavors out of foods that you would never experience in them fresh, let alone canned or frozen. Katz suggests that as you experiment with fermentation, which you will undoubtedly do after reading his book, that you cultivate cultures of sharing your various ferments with friends so you can all experience that palate pleasing textures, tastes and aromas of fermented foods.

In honor of that suggestion, I am providing a simple recipe for homemade sauerkraut below, which should be ready in time for Thanksgiving. Perhaps you will start a new tradition as you gather round with family and friends for this holiday meal and share a few jars of your own ferments.

The following recipe is for a 5-pound batch. You will probably need three to four medium/large heads of cabbage. When fully chopped and packed into its own brine, this amount of cabbage will fill about three quart jars or fit nicely into a large gallon container with room for a brine bag or weight.

Recipes for how to use your kraut can be found at: http://extension.oregonstate.edu/lane/sites/default/files/documents/sp50611making-sauerkraut.pdf.

Ingredients

5 pounds of shredded cabbage

3 tablespoons canning or pickling salt

Equipment needed

Fermenting containers should be food grade. One-gallon glass or plastic jars work well for a 5-pound batch. (Do not use copper, iron or galvanized-metal containers or garbage bags and trash liners.) Use a very large stainless steel or plastic bowl for mixing cabbage and salt before putting into fermenting container. For shredding cabbage use a large cutting board and sharp knife.

Making the sauerkraut

Select mature heads of cabbage that are disease-free. The best kraut is made from the mid- to late-season crop. When picking fresh it is best to wait one or two days after harvesting to make the kraut.

Kraut can be made from both red and green varieties.

For 5 pounds of shredded cabbage you will need between 6-7 pounds of fresh cabbage. Remove outer leaves and rinse heads with cold water and drain. Cut the heads in halves or quarters and remove the cores, trim and discard any damaged tissues.

Shred or slice cabbage using a sharp knife or kraut cutter. The shreds should be long and thin, about the thickness of a quarter. Place 5 pounds of shredded cabbage in a large bowl and sprinkle 3 tablespoons of salt evenly over cabbage. With clean hands thoroughly mix the salt into the cabbage. You will notice cabbage will begin to wilt as the salt is mixed in.

When all the salt is dissolved and the cabbage is juicy, begin packing the cabbage firmly into the food-grade fermenting container. Use your fist to firmly and evenly press the cabbage into the jar or crock. As you pack you will notice the juice coming from the cabbage. You will need enough juice to cover the cabbage. It is important to leave at least 4-5 inches of head space.

Once the fermenting container is adequately filled and the juice is covering the cabbage you are ready to put a weight on the kraut to keep the liquid covering the cabbage during the fermentation period. Be sure to wipe the edges of the jar or crock before putting the weight on top.

When fermenting in a glass jar you can weigh down the kraut using a freezer-weight plastic bag filled with brine made of 1½ tablespoons salt to 1 quart of water. For crocks use a plate and weigh it down with a jar of water or a plastic bag filled with brine. The amount of brine in the plastic bag can be adjusted to give enough pressure to keep the fermenting cabbage covered with brine.

Once the weight is in place, cover the fermenting container with a clean tea towel or cheese cloth to reduce mold growth. For glass containers you can cover the jar with a brown paper bag to keep the light off of the kraut while it is fermenting. This helps retain nutrients and also preserves the color of the kraut.

Fermentation temperature and management

Store at 70-75 degrees F while fermenting. At temperatures between 70-75º F sauerkraut will be fully fermented in about three to four weeks; at 60-65º F fermentation may take five to six weeks. At temperatures lower than 60º F sauerkraut may not ferment. Above 75º F sauerkraut may become soft. The smaller the fermenting container the faster it will ferment.

If you weigh the cabbage down with a brine-filled bag, do not disturb the crock until normal fermentation is completed. If you use a plate and jar as weight, you will have to check the sauerkraut two or three times each week and remove scum if it forms. A good test to see if kraut is ready is to smell and taste it. It should smell and taste like kraut, not sour cabbage.

Happy Preserving!

Lauren Kraemer is Extension Family and Community Health Faculty for Oregon State University/Wasco County Extension.